Over the last three to five years, regulations for siting, permitting, designing, constructing and operating a landfill have increased. While Subtitle D criteria have driven some of the regulatory changes, the states and professionals in the solid waste community also have played a critical role. In addition, ongoing research and the new political climate in Washington, D.C., greatly impact landfill issues.

Several trends have emerged over the past few years. For example, the industry and the public now seem to recognize the important role landfills play in solid waste management systems. Several years ago, many activists and recycling advocates claimed that, through recycling, landfills could be virtually eliminated. As the costs of recycling programs escalate and communities move toward integrated management systems, this argument has dissolved. Although efforts to recycle, reuse and minimize waste are important elements of a waste management program, they cannot stand by themselves.

The solid waste professional community has played a tremendous role in leading the way for landfill innovation. Fifteen years ago, landfills were not nearly as sophisticated as today's sites. Design professionals, material and equipment suppliers, regulators, communities, academia, professional organizations and environmentalists have worked together to develop new technology and regulations for each state.

This work is an ongoing, cooperative process that requires previous landfill experience, input from trained landfill operators and a substantial amount of research. For example, Florida, New York and Texas have established groups or forums to discuss new regulatory policies. Professional groups, including the Solid Waste Association of North America, the National Solid Waste Management Association, Environmental Protection Agency and the Industrial Fabrics Association International, hold conferences, seminars and training programs to further landfill discussion and research. Academic communities, including the University of Wisconsin and the University of Florida's Treeo Center, also add to the exchange of information on landfill design and regulation.

Meanwhile, healthy debate continues over many issues, such as models for liner system performance analysis. For example, most engineers use the EPA's Help Model to create their own site-specific liner system.

Overall, a greater understanding of the performance of modern landfills has emerged. In turn, this understanding serves as a common base for debating specific elements of design, such as the impacts of using geonets and other new synthetic materials. As a result of cooperative efforts and a widespread understanding of landfills, innovative designs including bio-reactor/bio-fill technology and mining can now be more fully evaluated.

In the future, each state will have the opportunity to adjust its rules and regulations to allow for innovative landfill methods. With this type of climate, landfills will become easier to permit, giving owners and operators even more ways to achieve their goals.